Alot of folks do not have the mindset for such things . What you ran into with the truck is typical of someone trying to do right but doing harm by doing so. A little knowledge is dangerous. I know my neighbors pretty well, most of them never change the oil in their small lawnmowers. Most of them still run well after a few years of this and the engine does not cause the loss of the mower it is the other things breaking or falling apart. The scrap yard here that takes mowers to junk has stacks of engines they sell to some buyer down south. My neighbor across the street has a small shed full of cheap lawnmower engines and other parts from folks who just drop a mower off at his place on their way to buy another. The young mother across from my fatherinlaw rolls her pusher over every spring to ask him to check the oil. She then mows all season with it. Most mowers get bought around here when income tax money comes back. Buying a new pusher every year or two is common due to bad carbs, or the wheels break.